# Exercising Bison on conflicts. -*- Autotest -*- # Copyright (C) 2002 Free Software Foundation, Inc. # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2, or (at your option) # any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA # 02111-1307, USA. AT_BANNER([[Conflicts.]]) ## ---------------- ## ## S/R in initial. ## ## ---------------- ## # I once hacked Bison in such a way that it lost its reductions on the # initial state (because it was confusing it with the last state). It # took me a while to strip down my failures to this simple case. So # make sure it finds the s/r conflict below. AT_SETUP([S/R in initial]) AT_DATA([[input.y]], [[%expect 1 %% exp: e 'e'; e: 'e' | /* Nothing. */; ]]) AT_CHECK([bison input.y -o input.c]) AT_CLEANUP ## ------------------- ## ## %nonassoc and eof. ## ## ------------------- ## AT_SETUP([%nonassoc and eof]) AT_DATA([input.y], [[ %{ #include /* We don't need a perfect malloc for these tests. */ #undef malloc #include #if STDC_HEADERS # include #endif #define YYERROR_VERBOSE 1 static void yyerror (const char *msg) { fprintf (stderr, "%s\n", msg); exit (1); } /* The current argument. */ static const char *input = NULL; static int yylex (void) { /* No token stands for end of file. */ if (input && *input) return *input++; else return 0; } %} %nonassoc '<' '>' %% expr: expr '<' expr | expr '>' expr | '0' ; %% int main (int argc, const char *argv[]) { if (argc > 1) input = argv[1]; return yyparse (); } ]]) # Specify the output files to avoid problems on different file systems. AT_CHECK([bison input.y -o input.c]) AT_CHECK([$CC $CFLAGS $CPPFLAGS input.c -o input], 0, [], [ignore]) AT_CHECK([./input '0<0']) # FIXME: This is an actual bug, but a new one, in the sense that # no one has ever spotted it! The messages are *wrong*: there should # be nothing there, it should be expected eof. AT_CHECK([./input '0<0<0'], [1], [], [parse error, unexpected '<', expecting '<' or '>' ]) AT_CHECK([./input '0>0']) AT_CHECK([./input '0>0>0'], [1], [], [parse error, unexpected '>', expecting '<' or '>' ]) AT_CHECK([./input '0<0>0'], [1], [], [parse error, unexpected '>', expecting '<' or '>' ]) AT_CLEANUP ## ------------------------- ## ## Unresolved SR Conflicts. ## ## ------------------------- ## AT_SETUP([Unresolved SR Conflicts]) AT_DATA([input.y], [[%token NUM OP %% exp: exp OP exp | NUM; ]]) AT_CHECK([bison input.y -o input.c --report=all], 0, [], [input.y contains 1 shift/reduce conflict. ]) # Check the contents of the report. AT_CHECK([cat input.output], [], [[State 5 contains 1 shift/reduce conflict. Grammar Number, Line, Rule 0 3 $axiom -> exp $ 1 3 exp -> exp OP exp 2 3 exp -> NUM Terminals, with rules where they appear $ (0) 0 error (256) NUM (258) 2 OP (259) 1 Nonterminals, with rules where they appear $axiom (5) on left: 0 exp (6) on left: 1 2, on right: 0 1 state 0 $axiom -> . exp $ (rule 0) exp -> . exp OP exp (rule 1) exp -> . NUM (rule 2) NUM shift, and go to state 1 exp go to state 2 state 1 exp -> NUM . (rule 2) $default reduce using rule 2 (exp) state 2 $axiom -> exp . $ (rule 0) exp -> exp . OP exp (rule 1) $ shift, and go to state 3 OP shift, and go to state 4 state 3 $axiom -> exp $ . (rule 0) $default accept state 4 exp -> . exp OP exp (rule 1) exp -> exp OP . exp (rule 1) exp -> . NUM (rule 2) NUM shift, and go to state 1 exp go to state 5 state 5 exp -> exp . OP exp [$, OP] (rule 1) exp -> exp OP exp . [$, OP] (rule 1) OP shift, and go to state 4 OP [reduce using rule 1 (exp)] $default reduce using rule 1 (exp) ]]) AT_CLEANUP ## --------------------- ## ## Solved SR Conflicts. ## ## --------------------- ## AT_SETUP([Solved SR Conflicts]) AT_DATA([input.y], [[%token NUM OP %right OP %% exp: exp OP exp | NUM; ]]) AT_CHECK([bison input.y -o input.c --report=all], 0, [], []) # Check the contents of the report. AT_CHECK([cat input.output], [], [[Grammar Number, Line, Rule 0 4 $axiom -> exp $ 1 4 exp -> exp OP exp 2 4 exp -> NUM Terminals, with rules where they appear $ (0) 0 error (256) NUM (258) 2 OP (259) 1 Nonterminals, with rules where they appear $axiom (5) on left: 0 exp (6) on left: 1 2, on right: 0 1 state 0 $axiom -> . exp $ (rule 0) exp -> . exp OP exp (rule 1) exp -> . NUM (rule 2) NUM shift, and go to state 1 exp go to state 2 state 1 exp -> NUM . (rule 2) $default reduce using rule 2 (exp) state 2 $axiom -> exp . $ (rule 0) exp -> exp . OP exp (rule 1) $ shift, and go to state 3 OP shift, and go to state 4 state 3 $axiom -> exp $ . (rule 0) $default accept state 4 exp -> . exp OP exp (rule 1) exp -> exp OP . exp (rule 1) exp -> . NUM (rule 2) NUM shift, and go to state 1 exp go to state 5 state 5 exp -> exp . OP exp [$] (rule 1) exp -> exp OP exp . [$] (rule 1) OP shift, and go to state 4 $default reduce using rule 1 (exp) Conflict between rule 2 and token OP resolved as reduce (%right OP). ]]) AT_CLEANUP ## -------------------- ## ## %expect not enough. ## ## -------------------- ## AT_SETUP([%expect not enough]) AT_DATA([input.y], [[%token NUM OP %expect 0 %% exp: exp OP exp | NUM; ]]) AT_CHECK([bison input.y -o input.c], 1, [], [input.y contains 1 shift/reduce conflict. expected 0 shift/reduce conflicts ]) AT_CLEANUP ## --------------- ## ## %expect right. ## ## --------------- ## AT_SETUP([%expect right]) AT_DATA([input.y], [[%token NUM OP %expect 1 %% exp: exp OP exp | NUM; ]]) AT_CHECK([bison input.y -o input.c], 0) AT_CLEANUP ## ------------------ ## ## %expect too much. ## ## ------------------ ## AT_SETUP([%expect too much]) AT_DATA([input.y], [[%token NUM OP %expect 2 %% exp: exp OP exp | NUM; ]]) AT_CHECK([bison input.y -o input.c], 1, [], [input.y contains 1 shift/reduce conflict. expected 2 shift/reduce conflicts ]) AT_CLEANUP